DESCRIPTION (Applicant's abstract): The theory of affective forecasting describes how people predict their emotional reactions to future events. The theory suggests that one's mental representation of a future event elicits both affective and cognitive reactions, and that these reactions are combined in particular ways to provide forecasts of one's future reactions. The model suggests that when making such forecasts, people often fail to consider (a) that they may be representing the event incorrectly (the misconstrual problem), (b) that their affective reactions to the representation may be poor proxies of their later affective reactions to the event itself (the contamination problem), (c) that their cognitive reactions to the representation may be wrong, incomplete, or underutilized (the miscorrection problem), (d) that their wishes and fears may have distorted their forecasts (the motivation problem), (e) that their minds will work to transform or "rationalize" negative affective states (the immunity problem), and (f) that other future events are likely to modify their affective states considerably (the vacuum problem). These problems may leave people susceptible to a variety of inferential errors (e.g., the durability illusion, the invisible hand illusion, the benevolent leader illusion, etc.). Eleven preliminary studies in both the laboratory and field support the basic predictions of the model, The present proposal describes sixteen new studies that use a variety of experimental and quasi-experimental paradigms to investigate the mechanisms that underlie affective forecasting as well its personal and interpersonal consequences. Past research has shown that the frequent experience of positive affect is a cornerstone of psychological well being. People can successfully attain such experiences only if they can predict the affective consequences of different courses of action. The theory of affective forecasting provides an explicit information-processing model that describes how such predictions are made and suggests a host of factors that should increase or decrease the accuracy of those predictions. If psychologists can learn how people predict and mispredict their own affective reactions to future events, they will be in a better position to help people make more accurate forecasts, and hence, personal choices that will enhance their psychological well-being.